In a 16-ounce mason jar, or other container, combine the rolled oats, pumpkin pie spice, chia seeds, milk, pumpkin puree, greek yogurt, milk, and pure maple syrup.
Stir all the ingredients together until the oats are completely covered with liquid. If needed, add more liquid until all the oats are covered.
Place the lid tightly on and store overnight in the refrigerator.
In the morning, add more liquid, if needed to loosen up the oats. Also, if you'd like to add a little more sweetener you can do it at this time too.
Sprinkle with pecans and/or cranberries and enjoy!